Removal of algae from biological cultures: a challenge for electrocoagulation?

BACKGROUND In the search for novel technologies for the treatment of urban wastewater, combined anaerobic–algae membrane bioreactors have become a very interesting choice. Recovery of algae produced in these reactors has become the key point to obtain a good economic efficiency with this technology....

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Detalles Bibliográficos
Autores: Souza, Fernanda, Cotillas, Salvador, Saez, C., Cañizares, Pablo, Lanza, Marcos RV, Seco, Aurora, Rodrigo, Manuel Andrés
Tipo de recurso: artículo
Fecha de publicación:2014
País:España
Institución:Universidad de Castilla-La Mancha
Repositorio:RUIdeRA. Repositorio Institucional de la UCLM
OAI Identifier:oai:ruidera.uclm.es:10578/29791
Acceso en línea:http://hdl.handle.net/10578/29791
Access Level:acceso abierto
Palabra clave:Algae culture
Electrocoagulation
Electro-flotation
Aluminum
Iron
Cultivo de algas
Electrocoagulación
Electroflotación
Aluminio
Planchar
Descripción
Sumario:BACKGROUND In the search for novel technologies for the treatment of urban wastewater, combined anaerobic–algae membrane bioreactors have become a very interesting choice. Recovery of algae produced in these reactors has become the key point to obtain a good economic efficiency with this technology. In this work, electrocoagulation is studied as an alternative for the coarse removal of algae from a biological culture. RESULTS Results demonstrate that the electrochemical technology is a suitable technology for this purpose allowing the removal of more than 90% of the algae without modifying significantly the pH and with an operating cost below 0.04 € m−3. The same general trends are observed for applied current charge and current density supplied when aluminum or iron are used as electrodes although aluminum was much more efficient. CONCLUSIONS The dose of coagulant reagents required is very low, indicating that coagulant generated in the process is very efficiently used. The best results in terms of algae and turbidity removals are obtained operating at low current densities with aluminum electrodes. According to pH and z-potential values, insoluble metal hydroxide and anion M(OH)4− seems to be the primary coagulation species involved in the electrocoagulation process.